/Engine/Source/Runtime/RenderCore/Public/RenderGraphBuilder.h
Queues a buffer upload operation prior to execution. The resource lifetime is extended and the data is uploaded prior to executing passes.
void QueueBufferUpload ( FRDGBufferRef Buffer, FRDGBufferInitialDataCallback && InitialDataCallback, FRDGBufferInitialDataSizeCallback && InitialDataSizeCallback, FRDGBufferInitialDataFreeCallback && InitialDataFreeCallback )